Anxious precursor to Apollo-Soyuz Test Project

摘要

In May 1975, the Soyuz 18b cosmonauts Pyotr Klimuk and Vitali Sevastyanov reconfirmed the integrity of the Soviet launch vehicle after Soyuz 18a failed a month earlier. Western observers followed the mission anxiously as the following Soyuz would fly the historic joint Apollo Soyuz Test Project (ASTP) mission. The Soyuz 18b mission was launched on 24 May 1975 from Tyuratam (Baikonur) in Kazakhstan. The crewmembers were the back-up cosmonauts of Soyuz 18a, which failed to enter Low Earth Orbit (LEO) due to a booster malfunction. Soyuz 18b entered LEO correctly and started to catch up with the Salyut 4 space station. On 26 May, transfer orbit completed, commander Pyotr Klimuk manually docked the Soyuz to the space station and entered the work compartment to start station activation.